Process for improving the tone quality and resonance of string instruments



Patented Apr. 10, 1951 UNITED STATES PATENT, OFFICE 31. 7 y PRooEss FOR IMPROVING THEVTONE QUAL- rrr AND RESONANCE OF STRING INSTRU- MENTS Ainedelis Dalmas, Oakland, Calif. Drawing. Application N oveinbe'r 10, 1947,

SerialNo. 785,196

3 Claims. (Cl. 144309) This invention relates to a wood processing technique which improves the tone quality and resonance of string instruments, such as violins, Violas, cellos, bass viols, guitars, mandolins,,ul;elele's' and the like, and a of particular value for violins and of utmost importance in connection with the bridge which in itself, when treated by my process, will greatly improve the tone quality of the instrument.

Violins are conventionally constructed of a variety of woods, and in the more valuable violins the back, neck sides and scroll, as also the bridge are usually formed of maple while the front or sounding board is usually formed of spruce, though for some parts rosewood and ebony are used, with the fingerboard and keys conventionally formed of ebony.

The woods are aged over a considerable number of years and are carefully selected for suitable grain, the parts are carefully formed, finished and assembled, and finally coated with a special type of varnish, all for the purpose of developing the utmost in tone quality and resonance, an attempt to duplicate the qualities of the Stradivarius, Amati and Guarnerius violins. However, it is known that no other violins have attained the beautiful tone quality of the Stradivarius, or the Amati or Guarnerius violins,

though the same types of woods have been used,v

and every effort made to duplicate those qualities.

My new process, even when applied only to the bridge of a violin, greatly improves the tonal quality even in the best violins made, and when applied to the entire violin, introduces qualities which appear to be identical to those of the originals of the old masters, Italian in character, deep and brilliant, and responsive to a degree equal to that of old instruments after years of continued use.

My process consists in using the same care in the selection of woods, together with suitable aging and finishing.

The bridge, when treated by my process, contributes more to tonal quality, resonance and true pitch, than any of the other parts of the violin, though when the bottom, sides and front of the sound box are also treated, the effect is outstanding.

The process consists in first forming the parts to size and shape, then boiling the parts in water until the wood is soft and pliable, then placing the parts between surfaces which are true to form and applying pressure and retaining a uniform pressure until the part is thoroughly dry, then removing the part and refinishing the edges as may be necessary.

Pressures vary with the wood used, softer woods such as spruce requiring a pressure of only about five pounds per square inch, while very hard woods such as rock maple or birdseye requiring a pressureup to about 25 pounds per square inch. The pressure is maintained constant throughout the drying period, which may require from two weeks up toseveral months. Drying is facilitated by maintaining a low heat, never up to the boiling point of water as steam must not be generated during the drying period. Furthermore, the pressure surfaces are preferably formed of material of a porous nature and may consist of aporous or spongy plastic or pumice or similar hard absorbent or porous material, though a noncorrosive metal may be used in which case drying takes place only from the edges unless the metal is provided with fine passages.

In the ordinary drying and aging process the sap evaporates leaving water soluble substances in the wood and which to some extent clog the celis and affect the resonance. Boiling removes these water soluble substances leaving the clear cellular structure with non-water-soluble binder.

The same species of wood in different specimens may show minor differences in density, and boiling in water expands the cells somewhat unevenly, while the application of pressure and maintenance of that pressure results in like densities when the weight is uniform for any specific variety of wood, and the wood is completely dried under that pressure.

With the soluble substances removed and the cellular structure made uniform, the tone quality is greatly improved, and this applies particularly to the bridge; It improves the tone quality of any of the conventional string instruments which use a wooden bridge or wooden sound box.

I claim:

1. The method of improving the tone quality of string instruments having a wood body and bridge consisting in finishing the respective parts of the body and the bridge to final size and shape, boiling the parts in water until soft and pliable, and placing the parts between porous forms conforming to the sizes and shapes of the respective parts, and exerting and maintaining a constant pressure while applying heat at a temperature below the boiling point of water until the respective parts are thoroughly dry.

2. The method of improving the tone quality of string instruments having a wooden body and bridge consisting in finishing the respective parts of the body and .the bridge to final shape and form ready for assembly, boiling the respective parts in water until the parts are soft and pliable and water soluble substances are removed, compressing the soft and pliable respective parts between porous surfaces conforming to the final shape and form of the respective parts under predetermined pressure while subjecting the parts to heat at a temperature below the boiling point of water to avoid formation of steam within the wood, and maintaining said heat and pressure uniformly until the respective parts are thoroughly dry.

3. The process of making a wooden part for a string instrument consisting in forming the part of seasoned wood to exact finished size and shape, boiling the part in water until the wood is soft and pliable, placing the soft and pliable part under pressure of 5 to 25 pounds per square inch according to the hardness of the Wood, in a pervious mold conforming to the size and form of the finished part while supplying heat to said part at a temperature below the boiling point of Water to prevent formation of steam within the wood, and maintaining said pressure and heat until the part is thoroughly dry, then removing 15 the part to provide a part for a musical instrument having exceptional quality of tone, resonance and pitch.

AMEDEUS DALMAS.

4 REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 77,777 Spaulding May 12, 1868 348,051 Pine Aug. 24, 1886 1,159,402 Markstein Nov. 9, 1915 1,328,506 Fish Jan. 20, 1920 1,419,440 Ashley June 18, 1922 1,794,194 Meyercord et a1. Feb. 24, 1931 1,994,607 Derby Mar. 19, 1935 FOREIGN PATENTS Number Country Date 102,562 Switzerland Dem 2, 1922 OTHER REFERENCES 

